before running build script, set ENABLE_ITAPS to 1 to turn on --enable-imesh, imeshp and --enable-igeom . iMesh-Defs.inc is installed when --enable-imesh is turned on . iMeshP-Defs.inc is installed when --enable-imeshp and --enable-imesh are turned on . iGeom-Defs.inc is installed when --enable-igeom is turned on